Time trip device



Nov. 28, 1961 H. w. HARRISON ET A1. 3,010,515

TIME TRIP DEVICE 5 Sheets-Sheet 1 Filed March 3l, 1958 QW@ n /-d-u7- W/ l C Y //A WJ M Z Z w HOM/w z mz m @mx mm A. m M M i /Z/ //////fZc/`/% HHHHHHH|||| lu ll if QJ:U7/\ mi) .@Z l

Nov. 28, 1961 H. w. HARRISON ETAL 3,010,515

TIME TRIP DEVICE 3 Sheets-Sheet 2 INVENTOR5 5/ l/\/. Hoff/son /0/7 M /f/n/ey C. /l//n/ey ATTO/@V575 Nov. 28, 1961 H, w. HARRISON ETAL 3,010,515

TIME TRIP DEVICE BY @,M

nite Ste This invention relates to time trip devices, and particularly to devices for providing a predetermined time delay in the operation of tools.

'Ihis application is a continuation-impart of U.S. patent application Serial No. 681,526 filed September 3, 1957, now abandoned.

It is an object of this invention to provide a new and improved device for providing a time delay in the operation of a tool.

An important object of this invention is to provide a new and improved device for use in a well tool or the like, wherein an actuating means is provided for initiating the operation of such tool, and wherein chemical means are also provided for effecting the tripping or release of said actuating means after a predetermined period of time.

Another object of this invention is to provide a new and improved time trip device in a tool for cutting a flexible line in a well bore or the like, wherein said device includes means for tripping or releasing a lock for said tool after a period of time, and wherein such period of time is determined by the time for a chemical reaction within the tool.

A particular object of this invention is to provide a new and improved time trip device, wherein a locking pin is provided which is capable of being dissolved or severed by a liquid chemical after a predetermined period of time, and wherein means are provided for contacting said chemical with said pin to initiate the chemical action on said pm.

The preferred embodiment of this invention will be described hereinafter, together with other features thereof, and additional objects will become evident from such description.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and where- FIG. 1 is a view, partly in elevation and partly in section, illustrating the device of this invention in use in a tool for cutting ilexible lines in a well bore or the like;

FIG. 2 is a sectional view taken on line 2--2 of FIG. 1 to illustrate the details of the time trip device of this invention;

FIG. 3 is a horizontal sectional view taken on line 3 3 of FIG. 5;

FIG. 4 is a vertical sectional view illustrating a portion of the structure shown in FIG. 2 after the liquid chemical has been released within the tool, but prior to the actual tripping of the device for actuat-ing the tool therewith; and

FIG. 5 is a view similar to FIG. 2, but illustrating the device of this invention after the chemical action of the liquid on the locking pin has caused the tripping or release of an actuating means of the tool for initiating the operation of the tool with which the device of this invention is used; f

FIG. 6 is a vertical sectional view of a modified time trip device; and

3,010,515 Patented Nov. 28, 1961 FIG. 7 is a horizontal sectional view taken on line 7 7 of FIG. 6.

In the drawings, the letter T designates generally a tool for cutting a wire line W or other flexible line. The tool T includes therewith the time trip device A (FIG. 2) of this invention, and such tool T is merely exemplary of various types of tools with which the time trip device A of this invention can be used. Briefly, the time trip device A includes a container 10-such as a Vglass bottle for a chemical in liquid form. The chemical is confined within the container 10 by a plug or closure member 11 and the container 10 is held in such closed position within the tubular body 12 of the device A of this invention, as will be explained more in detail hereinafter. The liquid chemical within the container 10 is released therefrom by fracturing the container 10 as indicated in FIG. 4 of the drawings so that such chemical contacts a time delay element or locking pin 15, the purpose of which will be hereinafter explained more in detail. The chemical is of such nature that it dissolves or severs the pin 15 after it is in contact therewith for a predetermined length of time, and when such predetermined length of time elapses, the actuation of the tool T or any other tool with which the device A is associated is accomplished. In the present form of the invention as illustrated in the drawings, the severing or dissolving of the pin 15 permits a spring 17 to move a plunger 18 downwardly for contact with a tiring pin 19.

The tiring pin 19 actually forms a part of the tool T for cutting the flexible line W, and such tool T is of the type illustrated in United States Patent 2,185,303 granted to M. M. Kinley. Such tool T includes a tubular body section 20 which is threaded or otherwise connected to the tubular body section 12 of the trip device A. Such body section 20 is illustrated as composed of several sections which are threaded together, but it will be appreciated that the entire body section 20 below the body section 12 (FIG. l) may be formed in one piece if so desired. A plunger wedge 21 having an inclined or wedge surface 21a at its lower end is positioned within the lower part of the tubular body section 20 and it is held in the position shown in FIG. 1 by its contact with a gripper member 22. Such gripper member 22 is releasably retained in a slot 20a by a shear pin 23. When the plunger wedge 21 is forced downwardly with sufficient force, it applies a lateral force to the Clamping member 22 to initially shear the pin 23 and then to move the member 22 outwardly in the groove 20a. Such action causes the clamping member 22 to move into gripping engagement with the flexible line or wire W. A cutter member 24, which is similar to the clamping member 22 is positioned below the member 22 and it is also held in a retracted position within a slot 2017 of the body section 20 by a shear pin 25. After the member 22 has been moved into contact with the flexible wire W, the plunger wedge 21 can continue downwardly so that the wedge surface 21a can contact the end of the cutter member 24 to initially shear the pin 25 and then to move such cutter 25 in the slot 20b for severing the flexible wire W. It will be noted that the llexible Wire W passes through a guide channel 26 so that the flexible wire W is confined within a relatively small tubular area to `effect the proper gripping with the member 22 and the proper cutting with the cutter member 24.

For moving the plunger wedge 21 downwardly, an explosive cartridge 30 such as a shotgun shell is positioned above the wedge 21 for contact by the firing pin 19. Additional explosive powder may be incorporated below the cartridge 30 if so desired. In any event, upon the firing of the cartridge 30 by the downward driving action of the tiring pin 19 against such cartridge 30, the exploa sive force on the upper end of the wedge 21 drives it downwardly with sufficient force to shear the pin 23 and to drive the clamping member 22 into contact with the exible Wire W. The member 21 is continued in its downward movement by the force imparted from the explosion so as to also shear the pin 2S to move the cutter member 24 into contact with the wire W for cutting or severing same. A stop shoulder 20c at the lower end of the body section 20 limits the downward movement of the plunger wedge 21 so as to hold the wedge member 22 in itsgripping or clamping contact with the wire W so that thereafter the wire W may be lifted to retract the tool VT from the well with the portion of the wire W above the point at which it was cut by the member 24.

Considering the details of the time trip device A of this invention, as particularly `illustrated in the drawings, such device A includes an upper head or adapter 35 which is threaded or otherwise connected to the body section 12 of the time trip device A. An annular seal, 36 formed of rubber or similar material is provided between the head 35 and the tubular body section 12 to prevent fluid leakage, as will be more evident hereinafter. The upper part of the head or adapter 35 is provided with a hollow bore 35a which terminates in a lower annular shoulder 35h. The lower part of the head 35' s threaded at 35e for receiving a bolt or screw 38 in threaded engagement therewith. The screw head 38a is preferably an Allen head which is longitudinally movable within the bore 35a as the screwr38is threaded in its threaded engagement with the threads 35e.y A suitable screwdriver or other tool is adapted to be insertedV within the bore 35a for engaging the screw head 38a tovturn such screw 38 relative to the head 35. The lower end of the screw 38 is in contact with a slidable stop member 40 which is preferably substantially cylindrical and which is formed with a reduced diameter portion 40a so as to provide a lower annular lateral shoulder 40b against which the spring 17 contacts. Preferably, the screw 38 is not connected with the stop member 40 so that relative rotation between the screw 38 and the member 40 is permitted while effecting a downward movement of the member 40 as the screw 38 is'rotated or turned. Thus, in the preferred form of the invention, the lower end 38b of the screw 38 is tapered or pointed so as to lit within a correspondingly tapered or pointed recess 40C in the upper surface of the stop member 40.

The spring 17 is ordinarily a coil spring and it is positioned with its lower end resting upon the upper surface of a flange 42 formed on the upper end of the plunger 18. Such flange 42 may be formed in numerous ways so long as space is provided between its outer edge and the internal surface of the bore 12a of the tubular body section 12 to permit liquid to ow therebetween. Thus, as illustrated in particular in FIG. 3 of the drawings, the flange 42 is formed with hat sides 42a which are spaced from Vthe bore 12a for the ow of the liquid in the container to the area below the ange 42l when such container 10 is broken or opened, as will be more evident hereinafter. A sharp point or fracturing projection 42b is preferably provided on the upper surface of the ange 42 for contact with the bottom of the frangible container 10 to assist in initiating the cracking or breaking t 4 n the liquid which is used for dissolving or chemically reacting therewith to sever or weaken same suflciently for fracturing the pin 15 to permit the downward movei ment of the plunger 18 relative to the body section 17.. AsV an example of materials for the pin 15, an acrylic resin or a polyvinyl acetate resin'may be used, and in such case a solvent such asV acetone,'methyl ac'etate,"ethylene `V dichloride, monomeric methyl methacrylate, or benzo peroxide, would be used as the,V liquid in the container 10 for contacting the pin 15 when desired. Otherrmaterials for the pin 15 and other liquids capable of chemically reacting with such pins 15 will occur to those skilled in the art and the invention is not limited to the particular materials given as an example.

The plunger 18 extends below the shoulder 12b` into a reduced diameter bore 12o of the body section 12'. A seal ring 45 Yformed of rubber or other similar sealing material is preferably mounted on the plungerj18vfor sealing contact with-the reduced diameter bore 12C to prevent fluid flow between the plunger 18 and the borev 12C. To be certain that the lower end 18b of the plunger 18 contacts the upper endv of the firing pin 19Vwith sufricient force to lire the cartridge 30, the air in the bore 12a below the lower end 18h of the plunger 18 is permitted to escape through a relief hole 18e. Such relief hole 18C extends upwardly from the lower plunger end 18b for the full length of the plunger18 (FIG-'2) and*V Y connects with a lateral relief hole 42C (FIGS. s2 and 3) in the flange 42 'so as to establish communication from the area of thebore 12b` below the seal 45 to the area of the bore 12a which is above the` seal 45. ItfshouldV be noted from FIG. 3 that Vthe longitudinal hole or passage 18c is displaced to one side ofthe -opening 18e v which s provided forV the rod 15 so that there is no4 i communication between the hole 18e and theopening 18a. However, Vif desired, Ythe hole 18e may'intersect with the opening 18a, in 4which case the hole 18C would be shortened so that it would only extend from VAtheend 18b or some other point below the seal 45, to the opening 18a. The portion of the hole 18e and the hole 42e could be lomitted withsuch a modification.Y

-If the hole 18C is formed as shown in the drawingsV v. and communicates with the hole 42e, it is desirable'to of such container 10 to effect the release of the liquid Y chemical therein. v

V'Ihe plunger 18 is locked or held in the raised position illustrated in FIG. 2 by the lock pin 15. Such pin 15 rests upon an annular lateral shoulder 12b which forms the lower end of the bore 12a. The plunger 18 is'ordinarily formed of metal and it is provided with an opening 18a therethrough for receiving the pin 15 which is usually made of a different material so that it is capable of being dissolved or severed by chemical reaction with the liquid in the container 10 after it is released therefrom and caused to contact such pin 15. The particular material of which the pin 15 is made will depend upon provide a removable plug 50 formed of cork, rubber or other similar material. Such plug 50 is inserted into the outer end of the hole 42e to close same for preventing .liquid from the container 10 from flowing downwardly through the relief holes 42a and 18C.'` Ordinarily, the level of the liquid in the bore 12a is below the flange 42 sov that a chemical reaction between such liquid and the plug 50 does not occur. If such-a chemicalreaction should be desired, however, the lateral hole 42C could-r be located in the plunger 18 belowvthe liquid level assumedV in the'- boreV 12a aftersuch liquid is released from the container 10'. In the event the structure is modified as proposed above to form the hole 18s so as to intersecztV with the opening 18a, the rod 15 would serve as a plug 'until 1t was' severed Yor sufficiently dissolved to permit liquid to ow around the rod 15 in the opening 18u tothe hole 18e.- The sealing between the rod 15 and the walls of the opening 18a would normally prevent theliquid tlow until the rod 15 is severed` It should be noted jthat in this form of the invention illustrated in thepdrawings, the upper end ofthe firing pin 19 extends into the lower portion of the reduced diameter bore 12a sov that when the pin 15 is severed or fractured so as to permit the plunger 18 to moveV downwardly, the lower endiof the plunger 18 can move into contact with the tiring pin 19 for effectingpthe tiring of the cartridge 30. It should also be noted that the pin 15 retains the flange 42 at a Y sufficientr elevation within the bore 12a.l so thatV the springV 17 is confined-between' the tiange 42 Vand the lateral'surface 40b of the stop member 40 in a compressed condition. Therefore, when thepin 15 Vis released by the chemical action with the liquid in the container 10, thek spring 17 forces the plunger 18 downwardly to contact its lower end with the firing pin 19. Also, further compression-of the spring 17 is accomplished during the lowering of the stop member 40 for fracturing the container 10 to release the chemical therein. Such additional compression of the spring 17 is also utilized in the downward movement of the plunger 18 for contacting the firing pin 19.

In the operation or use of the time trip device A of this invention in the cutting tool T as illustrated in the drawings, the tool T is initially positioned on a flexible wire W at the surface of a Well. In well operations, various well tools are lowered on a llexible line such as the wire line W illustrated in the drawings and, in some instances, such tool at the lower end of the ilexible line W may become lodged or caught in the well bore so that it is impossible to retrieve it by pulling upwardly on the wire line. In such case, it becomes necessary to sever the line at some inaccessible point within the well bore so that the wire line may be salvaged and so that some other type of shing tool may be inserted to recover the tool or equipment which was lowered originally on the ilexible line W. Thus, assuming the wire W is in a well bore and is connected with a tool or piece of equipment in the Well bore which is lodged or caught so that it cannot be retrieved with the wire line W, then the tool T illustrated in the drawings would be used. The tool T would .beA inserted over the upper end of the wire W at the earths surface, usually in the vicinity of the well derrick, so that the wire line or other ilexible line W extendsthrough the guide sleeve 26 as shown in FIG. 1 of the drawings. The tool T is then in a position for dropping or lowering Within the Well bore or pipe by gravity until it reaches the upper end of the tool connected at the lower end ofthe Wire line W.

With the time trip device A of this invention, a screwdriver r other tool is positioned within the bore 35a foi-'turning or rotating the screw 38 either just prior to or just after the positioning of the tool T on the line W. The rotation of the screw 38 causes the stop member 40 to move downwardly relative to the tubular body section 12. Since the lower end of the container or bottle is resting upon the ilange 42, the downward movement of the stop member 40 imparts a compressive force to the container 10 and such compressive force ultimately becomes sufficient to fracture the container 10. f As previously stated, the container 10 is preferably made of glass or other similar frangible material. The container 10 has liquid or chemical therein and since the container 10 is securely held in a position shown in FIG. A2 between the member 40 and the ange 42 prior to the fracture thereof, the release of such liquid is prevented until the container 10 is fractured or broken. The fractured container 10 is illustrated in FIG. 4. The liquid ows from the fractured bottle 10 downwardly past the ilange 42 due to the fact that the spaces between the ilange 42 and the bore 12a are provided by the flat spaced surfaces 42a of the flange 42. 'Ihe chemical in liquid form thus collects in the bore 12a in contact with the rod or pin 15. The seal 45 prevents the fluid from owing downwardly and out of the chamber provided thereabove within the tubing section or body section 12. The seal 36 at the upper end of the body section 12 also prevents the escape of the liquid from the interior of the section 12 in the event the tool is shaken or inverted after the liquid is released from the container 10. The liquid which is released from the container 10 is capable of dissolving or etching the pin or rod 15, and a partially dissolved rod is illustrated in FIG. 4. The rod or pin 15 ultimately becomes suiliciently weakened so that the spring force applied thereto by the spring 17 effects a shearing or severing of the rod or pin 15. As previously mentioned, the spring 17 is placed under additional compression when the screw 38 is rotated for breaking or fracturing the container 10. The force of the spring 17 is then relatively great and it applies a continuous downward force to the pin 15 which is normally insufficient to fracture the pin 15, but when the pin 15 has been subjected to the chemical action by the released liquid within the section 12, then the spring force 17 is sufficient to fracture or shear the pin or rod 15.

The strength of the solution of the liquid in the container 10 and the size of the rod 15 can be controlled in accordance with the time delay which is desired priorto the movement of the plunger 18 downwardly. Of course, the rod 15 must be at least of sufficient strength to resist fracture during the initial breaking of the glass or frangible container 10, but it may vary in thickness from such minimum thickness s-o that greater lengths of time or lesser lengths of time before the chemical liquid reacts with the pin 15 can be obtained prior to the shearing or severing of the pin or rod 15. The time delay is desirable in connection with the cutter tool T illustrated in the drawings in order to per-mit the tool T with the time trip device A to fall from the ground level down into the well bore the full length of the ilexible line or wire W. As is well known, wells are of extremely great `depths in many instances and it therefore requires a considerable amount of time for a tool such as the cutter tool T to reach the bot-tom of the wire W in contact with the upper end of the tool connected with such wire W. During the descent of the tool T the liquid or chemical is reacting with the rod or pin 15 so that after the tool T has reached its lowermost position at which it is desired to cut the wire line W, the tool is actuated for elfecting the clamping and cutting of the wire line W.

Thus, after the screw 38 is manipulated at the surface of the well or the ground level to release the chemical or liquid from the container 10, the entire tool T is dropped by gravity so that it slides downwardly along the wire line W. The predetermined length of time that it takes for the liquid to react with the rod or pin 15 in order to sever or `shear same is always suflicient to permit the tool T to fall into contact with the tool or equipment attached at the lower end of the wire W, and preferably there is sufficient time delay after the tool T reaches the lower end of the wire W before the tool T is actuated so that premature actuation of the t-ool T and therefore premature cutting of the wire line W is prevented.

When the tool T has reached the tool or equipment at the lower end of the wire line W and is therefore halted in its descent on the wire line W, the tool T remains in that position until such time as the acid or other liquid sutIi-ciently dissolves or reacts with the rod or pin 15 to enable the spring 17 to impart the downward shearing force to the pin 15 for shearing or severing same.

When the shearing of the pin is accomplished by the chemical reaction, the spring 17 forces the plunger 18 downwardly into contact with the upper end of the firing pin 19 so as to lire the cartridge 30 and the explosive powder therewith. As the plunger 18 moves downwardly, the air in the bore 12C below the seal ring 45 is gradually compressed unless such air leaks upwardly past the seal ring 45. If such compression occurs, the plug 50 is forced out of the hole `42e` lto thereafter permit the llow of the air upwardly through the holes 18c'to 42C to thereby relieve the pressure which would otherwise develop in the bore 12e below theplunger 18. By so relieving such pressure, the full force of the spring 17 is transmitted from the plunger 18 to `the tiring pin 19 to be certain that a sufficient impact is imparted to the ring pin 19 to fire the cartridge 30 and the explosive powder. It will be understood 4that if the hole 18C intersects with the opening 18a in the modification as proposed above, the air below the plunger 18 will escape or be relieved through the hole 18e and opening 18a as the plunger 18 is forced downwardly by the spring 17. In any event, the explosion `of the powder causes the wedge 21 to move downwardly so that the wedge 21 7 lrst applies a sufficient force to the clamping member 22 to shear the pin 23 andy then the wedge 21forces the member 22 out into gripping engagement w1th the wire W. The downward movement of the wedge member 21 is continued by the explosive force acting thereon so that the pin 25 is next sheared and the cutter member 24 is forced outwardly to sever or cut the wire W. The downward movement of the wedge member 21 is preferably halted by its contact with the shoulder 20c or other stop surface so that the cylindrical portion of the member 21 holds the clamping member 23 in gripping engagement with the wire W. Thereafter, the complete tool T can be lifted by raising the flexible line or wire W at the surface of the well, so that the wire W is recovered and the tool T is also recovered.

vIn FIGS. 6 and 7, a m-odied construction is illustrated wherein the time trip device A is utilized instead of lthe time trip device A of FIGS. 1-5 with a tool such as the cutting tool T. The tool A includes a sleeve housing or tubular body 112 which corresponds with the body 12 of FIG. Z and which also is adapted to connect with 4the upper end of the housing or body section 20 of the cutting tool T in the event such time trip'device A is used therewith. YIt will be understood of course that when the time trip device A is used with the tool T, the time trip device A is not used. Y

The time trip device A has a tubular head 13-5 connected to the upper end of the body or housing 112 in the same manner asV the head 135 is connected with the body V12. An annular seal or O-ring 136 of rubber or other similar lsealing material is provided to prevent iluid flow at `the connection between the bodyV 112 and the head 135 (FIG. 6). An operating screw 138 corresponding to screw '38 in FIG. 2 is threaded in engagement with internal threads 135C so that by engagingthe head V13:8[1 of the screw 138, such screw 13'8- may be moved upwardly or downwardly as desired. A substantially cylindrical block manner as the block 40 in FIG. 2. Such Iblock contacts a plug or closure member lllwhich serves to close the upper end of a bottle or container 110. The lower end of the bottle 110 rests upon a fixed support 118 which has Va relatively sharp point 118a in engagement with the lower surface of the bottle or container 110. Such support 11S is an integral part of the body 112, or is xed thereto in any desired manner so that thebottle 110 is held firmly between the fixed support 11S` and the block 140 when the screw 138 is turned downwardly a suflicient amount. Also, when desired, as will be more fully explained, the bottle or container 110 is fractured or broken to release the contents thereof by applying a Sullicient downward force `on the bottle or container 110 with the rotation of the screw 138 in a downward direction.

A plurality of openings or channels extend downwardly from the main chamber. .1l-2a of the housing 112 and such openings are identified with the numeral L12b. Such openings or channels 112b provide for the ow of the liquid from the container 110` after it has been released therefrom to the cham-ber 112C at the lower portion of the body 112. Prior to the release of the liquid from the bottle or container 110 by the fracturing thereof, the openings or channels 112b are maintained closed with a plate L15 which is annular in shape in the form illustrated in FIG. `6 of the drawings. Such plate 115 is formed of a material which is capable of being dissolved or severed by chemical reaction with the liquid which is released from the bottle or container 110. Therefore, the time required for the dissolving or severing of the plate 115 after the contents of the bottle or container 110 has been released into the chamber 112a is the time required for the contents or liquid from the bottle or container 110 to pass .through the plate L15 and downwardly into the chamber 112C. The chamber 112e has 140 is mounted below the screw 138 in the same 110vso as` to cause an explosive force.. In theprefcrred. .Y

formof the invention therefore, the contents of the bottle or container 110 is picricv acid and the, material 9S. 1s sulfuric acid in liquid form, and theplate 1151 is copper. So long as the picric acid and the sulfuric'acid are. sepaa rated from each other, there is no. danger of an explosion occurring from such materials, but when they react with each other, they react suliicientlyl violently to create anexplosive force 'which s utilized in connection with this invention, as will be explained.

The material is confined within the chamber 112e by a plate or diaphragm 96 so as to separate suchmaterial 95v from the explosive powder charge 130 positioned- Ytherebelow. Such charge 130 is positioned at'the upper end of the wedge 21 which is ordinarily constructed in the same manner as the wedge 21'ofV FIG. 1 of the drawings. The explosive powder, charge 130 takes the place of the powder charge 30 illustrated'in FIG. l. Therefore, when the p-icric acid has vdissolved the copper and has passed into contact with the sulfuric acid, 'they chemically react to create the initial explosion and such explosion is sufficient to fracture or `blow the diaphragm 96' downwardly to ignite and explode the powder charge 1301. The explosive force created by the powder charge 13() then drives the wedge 21 downwardly relative to the body 20in the same manner as previously described in connecu tion withithe form of the invention shown ill-FIGS. 1 5,

The operation of .the form of the invention shown' in FIGS. 6 and 7 is believed evident frv m the foregoing description.Y tool such as the line cutting ltool T' of FIG. l in place of the time trip deviceA illustrated therein, Under such circumstances, the screw 1318 Vis turned'with a screw driver or other toolat the Vsurface of thewell prior` to the lowering of the tool T on the llexi-ble Vwire line W so4 that the liquid `or contents of thev container .110 is" released.v The liquid within the. container 11.0, when released, is of such a nature that it can dissolve or other-V wise sever the plate 115.' ,The plate 11,5 can be metal or it can be formed of the` materials referred to above in 1 connection with thelock pin 15 so long as such material liquid which is within rthe container 11 leased therefrom. Thethickness of the material 115 and the nature thereof with respect .to the liquid in con,.- taner will determine the time delay provided byY this time trip device A. dissolved or severed the plate suciently to.` permit the passage of the liquid through the openings 112k to the chamber 112e, the liquid comes into contact with the material explosive force detonates -t-he powder charge 13.0.for mov, ing the mandrel 2.1 downwardly as explained in co tion with FIG. 1. When the wire line W has been severed and. gripped as Aexplained in connection with FIG. 1, then the. complete tool with the time trip device A thereon may be removed from the well by lifting the wire line W upwardly. k f i It can thus be seen that with the` time trip devices A and A of this invention, it is unnecessary tofdrop any Ycal is to be used, the chemical is prevented fromy being itsv container 10 orv L10 bccause such containers 10vand,110 lare fractured only Yby the positive movement of .the screws 3,8 and 138 down'- inadvertently released from wardly, which requires `theturning of such screws- 38 and 138 with a screwdriver or other tool.

The time trip device A is mounted on a When the acid or other liquid has 95 for creating the explosive force. Such Y Although the timetrip devices A and A are particularly desirable and useful in connection with the cutter tool T, as explained above, they are also useable in connection with any other type of tool wherein it is desired to delay the actuation thereof for a predetermined length of time.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. A time trip device comprising, a tubular body, a plunger longitudinally movable in said body, a lock pin for normally preventing longitudinal movement of said plunger in one direction relative to said body, a container positioned on said plunger for holding a chemical therein capable of reacting with said lock pin for effecting a release thereof,'means for releasing the chemical in the container therefrom for contact with said lock pin, and means for applydng a longitudinal force to said plunger after said pin is sufficiently weakened for severing same.

2. A time trip device comprising, a tubular body having a chamber therein with a longitudinal opening therebelow, a plunger extending into the lower end of said chamber and longitudinally movable in said longitudinal opening, a seal ring on said plunger in sealing engagement with the wall of said longitudinal opening for maintaining a seal at the lower end of said chamber at all times, a lock pin for normally preventing longitudinal movement of said plunger in one direction relative to said body, resilient means for urging said plunger in said one direction which is normally insufficient to sever said lock pin, means within said tubular body for weakening said lock pin within a predetermined period o-f time so that the force applied to said plunger and lock pin is then suicient to sever said lock pin to move said plunger in said one direction.

3. The structure set forth in claim 2, including means for increasing the force applied by said resilient means at the beginning of said predetermined period of time.

4. The structure set forth in claim 2, wherein said lock pin is made of an acrylic resin, and wherein said means for weakening said lock pin is a liquid chemical capable of reacting with said acrylic resin to dissolve same at a portion thereof for weakening same.

5. In a tool for severing a flexible line in a well or the like having cutter means for severing the exible line and explosive means for moving said cutter means into cutting engagement with said flexible line, the improvement residing in a time trip device comprising, a tubular housing having a chamber therein, a container in said chamber and separate therefrom for confining a chemical in said housing for handling therewith without danger of losing or releasing same prematurely, a support means in said e housing for supporting said container, a movable head engageable with the upper end of said container for squeezing said container between said head and said support for releasing said chemical in said housing, and means capable of reacting with said chemical after its release in the housing for initiating a detonation of the explosive means after a predetermined period of time.

6. The structure set forth in claim 5, wherein said last-named means comprises a lock pin.

7. The structure set forth in claim 5, wherein said last-named means comprises a closure plate.

8. A time trip device comprising, a tubular body having a chamber formed in the bore thereof, a support in said `chamber adapted to move longitudinally relative to said body, a frangible container for conning a chemical therein Within said chamber and positioned on said support, a movable head in engagement with the upper end of said container to hold said container between said head and said support, -a time delay element within said chamber and connected to said support for preventing longitudinal movement of said support and adapted to v be contacted by the chemical from said container when said container is fractured for releasing said support for longitudinal movement, a resilient member extending from said support to said movable head and surrounding said container, and actuating means for moving said movable head relative to said support to squeeze said container for fraoturing same and for compressing said resilient member, whereby said chemical is released so that after said time delay element is acted upon by said chemical said support is longitudinally moved in said body by said resilient member.

9. The structurer set forth in claim 8, wherein said actuating means is positioned in the bore of said tubular body and is accessible from the exterior thereof.

10. The structure set forth in claim 2, wherein said plunger has a relief port for preventing a uid lock when said plunger moves longitudinally in said opening.

11. A time trip device comprising, a tubular body having =a chamber formed therein, a plunger longitudinally movable in said body, a frangible container supported on said plunger and having a chemical therein adapted to be released upon a fracturing thereof, a lock pin for normally preventing longitudinal movement of said plunger in one direction relative `to said body, means for fracturing said container to contact said lock pin with the chemical from said container for reacting therewith for weakening said pin sufficiently for severing same to release the plunger from the body for longitudinal movement relative thereto in said one direction after the predetermined time required for such chemical reaction, and means for applying a longitudinal force to said plunger in said one direction which is insufficient to normally sever said lock pin but which is sufficient to sever said lock pin after it has been weakened by said chemical reaction.

12. A time trip device comprising, a tubular body having a chamber formed therein, a plunger longitudinally movable in said body, alfrangible container supported on said plunger and having a chemical therein adapted to be released upon a fracturing thereof, a lock pin for normally preventing longitudinal movement of said plunger in one direction relative to said body, means for fracturing said container to contact said lock pin with the chemical 'om said container for reacting therewith for weakening said pin sufficiently for severing same to release the plunger from the body for longitudinal movement relative thereto in said one direction after the predetermined time required for Isuch chemical reaction, and a spring for applying a longitudinal force to said plunger in said one direction which is insufficient to normally sever said lock pin but which is sutlicient to sever said lock pin after it has been weakened by said chemical reaction.

References Cited in the file of this patent UNITED STATES PATENTS 242,675 Moore June 7, 1881 1,337,525 McAlpine Apr. 20, 1920 1,813,368 Toles July 7, 1931 1,898,073 Woodberry Feb. 21, 1933 2,185,303 Kinley Jan. 2, 1940 2,655,993 Spencer Jan. 22, 1948 

